1. Field of the Invention
The invention relates to a suction float to remove liquid and/or foam-like contaminants from the surface of liquids. Further, the invention relates to a collection device with a suction float and a collection vessel.
2. Description of the Related Art
Contamination on surfaces of liquids could be liquid or foam-like. Examples of contaminants include substances such as oil, crude oil, bound oil, foams, chemicals and contaminants of all types, as well as garbage, wherein the impurities swim or drift on the liquid, for example water or the like in machine holding pools, water reservoirs, settling tanks, ponds, lakes, rivers or oceans.
Seas, lakes or rivers are contaminated and polluted with industrial residues, oils or other wastes. These impurities float to the surface and must be removed. Ponds are contaminated, for example, by leaves or other plant debris. Machine holding pools can include, for example coolant liquids which become contaminated with oil or the like during the working process.
Different arrangements are known from the prior art to remove impurities on the surfaces of liquids.
Standard means for extraction of contaminants from surfaces of liquids include, for example, vacuum pumps which draw large amounts of fluid besides the actual contaminants. Alternatively, absorbents, such as binders or natural fibers, such as cotton, are used in order to bind the impurities for later collection in firmer bound form.
For further treatment of the suctioned-off impurities and liquids, there are known for example oil separators or light liquid separators or even gasoline separators, which deposit the suctioned-off impurities in an appropriate subsequent treatment facility for separation of the impurities from the fluid, thereby to remove the impurities found on the surfaces of liquids.
Next, different arrangements for removing contaminants from the surface of the sea or inshore waters are known in the prior art to combat oil spills and spills of oil rigs or tankers at seas and inshore waters.
Oil floating on the water surface can be skimmed using specialized vessels, folding boats, conventionally designed boats with outriggers, catamarans or mixed constructions with a catamaran bow. For this purpose there is known, for example, in the prior art a double hull vessel “Thor” of which the two vessel halves open from the bow to 65 degrees for receiving oil, whereby an open triangle is formed in which the oil collects. At a low operating speed the oil is forced through openings in the two ship halves, separated by separators, and pump with charge into the cargo tanks. The actual receiving devices may be based on the principle of a dam over which the oil flows, or an oil adsorbent layer with revolving rollers, or brushes with strippers, which gather the impurities.
After skimming, the oil which still contains water is further purified by means of separators, wherein the water is largely removed. For low and high oil viscosities, partially differing pumping systems are used.
Also known generally in the prior art are skimmers. A skimmer is a device in artificial lakes, ponds or pools and other liquid bodies, which sucks the dirt from the surface. Dust, leaves, oil or other contaminants cause the pond or sea water to become enriched with too many nutrients from the outside and thus overgrown with algae and cloudy. A skimmer in a pond or lake prevents this process and can prevent that the surface contamination causes the water to become cloudy. In larger bodies of water a proportionately larger number of water extraction points is installed. Skimmers can also be used, for example, to clean cooling water. Skimmers have a large diameter pipe positioned vertically in the liquid, wherein the diameter of the pipe is greater as it nears the water surface. Via a pipe connection, to which a suction pump is connected and in which a coarse particle filter or a sieve is attached, the skimming off of impurities from the surface of the liquid is accomplished.
Another field of application of appropriate extraction systems is in the industry. To obtain stable cooling lubricants in the machining industry, the required concentrate must be thoroughly mixed with water. Systems are available for the separation of unwanted oils, which can quickly separate the undesirable oils and other contaminants, for example, cutting lubricating fluids, without changing the base fluid. For this purpose suction floats or snorkel floats are used for the extraction, which are arranged in a liquid reservoir.
DE 3916026 A1 discloses an apparatus for collecting gasoline, oil and similar materials floating on the water, the apparatus comprising a dam made up of floating bodies and having a skimmer connected to a pump. Box-shaped wall elements form the floating body, which sink to approximately half their depth in the water and have a tall elongated rectangular cross-section shape. For the form-stable connection of the individual wall elements, plug-in elements are provided at both ends.
Further, an apparatus for removing floating substances such as oil, foam, and the like is known from DE 2407409 A, wherein a main floating body having through-channels for receiving floating substances is provided, with a buoyant housing or buoyant structure, wherein the buoyant housing or structure is movable up and down relative to the main floating body. By means of this device oil, foam and the like, for example, floating on the water of rivers, lakes, the sea water, of liquid surfaces in settling tanks, water tanks and the like can be removed.
Problems of the known prior art suction devices:
With known deep-sea systems, the efficiency of present systems is already very limited in rough seas of 1 meter wave height, and from 2 meters they are no longer useful. This means they can be employed to a maximum wind force 4. Since the impurities must however be removed even in stronger winds, this needs to be improved. Similarly, the use of speed is limited to 1 to 2 knots. The collecting widths are, in the larger vessels, up to 40 meters.
In other application areas, such as industrial plants or other aquatic bodies, adaptability to changing liquid levels is relatively difficult, so mostly a manual adjustment is required.